Exploring alternative manufacturing techniques for high-quality solar cell interconnectors: a comparative study of laser cutting and electric discharge machining

Abstract

Abstract Solar cell interconnectors are typically crafted from thin foils to establish an electrical connection between two components. For limited production of interconnectors with non-standard dimensions, common production methods (such as stamping and sheet metal processes) cannot be utilized. This article examines alternative techniques, such as Fiber Laser Cutting Machine and Electric Discharge Machining (wire cutting). The laser cutting method did not achieve the desired quality standards, leading to the rejection of the interconnectors. Issues such as burning, local melting, and damage to the silver coating were noted at the edges. The melting of the coating layers formed brittle intermetallic compounds, which can cause cracking and reduce weldability and solderability. In contrast, the Electric Discharge Machining method successfully produces interconnectors with complex shapes by stacking layers of foil. This approach results in high-quality interconnectors that showed no signs of burning or local melting on their edges.